EP 2023342 A1 20090211 - Noise reduction with integrated tonal noise reduction
Title (en)
Noise reduction with integrated tonal noise reduction
Title (de)
Geräuschunterdrückung mit integrierter Unterdrückung tonaler Geräusche
Title (fr)
Réduction de bruit avec une réduction des bruits sonores intégrée
Publication
Application
Priority
- US 95192207 P 20070725
- US 96171507 A 20071220
Abstract (en)
The system provides a technique for suppressing or eliminating tonal noise in an input signal. The system operates on the input signal at a plurality of frequency bins and uses information generated at a prior bin to assist in calculating values at subsequent bins. The system first identifies peaks in a signal and then determines if the peaks are from tonal effects. This can be done by comparing the estimated background noise of a current bin to the smoothed background noise of the same bin. The smoothed background noise can be calculated using an asymmetric IIR filter. When the ratio of the current background noise estimate to the currently calculated smoothed background noise is far greater than 1, tonal noise is assumed. When tonal noise is found, a number of suppression techniques can be applied to reduce the tonal noise, including gain suppression with fixed floor factor, an adaptive floor factor gain suppression technique, and a random phase technique.
IPC 8 full level
G10L 21/02 (2006.01); G10L 21/0208 (2013.01)
CPC (source: EP KR US)
G10L 15/20 (2013.01 - KR); G10L 21/02 (2013.01 - US); G10L 21/0208 (2013.01 - KR); G10L 21/0216 (2013.01 - KR); G10L 21/0232 (2013.01 - EP); G10L 2021/02085 (2013.01 - EP US)
Citation (applicant)
EPHRAIM, Y.; MALAH, D.: "Speech Enhancement Using A Minimum-Mean Square Error Short-Time Spectral Amplitude Estimator", IEEE TRANS. ON ACOUSTICS, SPEECH, AND SIGNAL PROCESSING, vol. 32, no. 6, December 1984 (1984-12-01), pages 1109 - 1121
Citation (search report)
- [A] EP 1703494 A1 20060920 - EMMA MIXED SIGNAL CV [NL]
- [A] WO 2006122388 A1 20061123 - HARMAN BECKER AUTOMOTIVE SYS [CA], et al
- [X] US 5706395 A 19980106 - ARSLAN LEVENT M [US], et al
Designated contracting state (EPC)
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MT NL NO PL PT RO SE SI SK TR
Designated extension state (EPC)
AL BA MK RS
DOCDB simple family (publication)
EP 2023342 A1 20090211; CA 2638265 A1 20090125; CA 2638265 C 20130618; JP 2009031793 A 20090212; KR 20090012154 A 20090202; US 2008167870 A1 20080710; US 8489396 B2 20130716
DOCDB simple family (application)
EP 08012861 A 20080716; CA 2638265 A 20080723; JP 2008186578 A 20080717; KR 20080072811 A 20080725; US 96171507 A 20071220